Quoting FlyingColours:Haha I once had a guy tell me that he knew the 737-400 could take off from ACE on "that" runway at "this" temperature because the winds never change and we were only going to divert for fuel because "our" airline couldn't afford to buy it in ACE so we would go to LPA where it is cheaper......

This was in response to the suggestion that, because passengers are more vocal these days, some accidents may have been avoided if they had given information to the flight crew which was otherwise unavailable to them. Specifically, we were talking about what would have happened at Kegworth if the SLC had piped up when they heard the captain's incorrect announcement.

So, has anyone here - private pilot or otherwise - ever had information from the FAs or the customers that has been helpful?

I once flew a Cessna 210 to FLG on a bright, sunny morning. Once established downwind in the pattern, I went through my GUMP check (Gear, Undercarriage, mixture, prop) which is standard for a high-performance complex single. About abeam the numbers, the Tower controller tells me "Centurion Zero Six X-ray, you are trailing smoke" which my passengers plainly hear over the radio (everyone is on headsets). I knew exactly what was happening: because of FLG's high field elevation, setting the engine's mixture to full rich made the exhaust quite smoky. I proceeded to lean the mixture somewhat, and responded to the tower "Tower, Zero Six X-ray, did that take care of the smoke problem?" The tower responded "Zero Six X-ray, affirmative", to which I responded "I put the mixture at full rich in preparation for landing. At this altitude, it will look a little smokey."

After landing, at least one of my passengers stated that yes indeed, she was a little freaked by the tower's transmission. As a captain, even if it is just for piston singles, I welcome outside input up to a point (especially in matters involving safety of flight), however the point of freaking out others is, at the very least, bad taste. There is no reason to needlessly raise your fellow pasenger's heart rates

Quoting David L (Reply 4):Innocent question: I take your point but how else would the tower check that everything was OK? Or do you mean the guy in the tower should have been aware of the phenonenon?

(Waiting for IAHFLYR or ATCT to chime in here ) not all tower controllers are pilots. I'd go out on a limb an say most of them aren't However, I would think that a tower controller at a high altitude airport had probably observed a few complex single-engined aircraft do the same thing at "their" airfield...

I'd much rather have them point it out every time my aircraft smokes rather than assume it is normal once when it isn't.

If you know you're going to be trailing a bit of smoke, why not brief your pax on it beforehand, along with everything else which could be perceived as abnormal during the flight? And if they are not familiar enough with flying not to be disturbed by what could be considered routine flight safety communication and if that is a problem, why not cut them out of the ATC comms?

I thought I was doing good trying to avoid those airport hotels... and look at me now.

Quoting BAe146QT (Reply 2):I don't get to wander around aircraft much since nurse took my CAA badge away, but I can't visualise what you're talking about.

If you look at the flaperon here: http://www.pbase.com/cityflyer/image/40855033/large.jpg. They are not that apparent in the pic but the outside edges of the flaperon have rubber insulating strips. I guess they seal any gaps between the flaperon and the flaps when the wing is clean.

I saw this insulation come loose and flap around for a few hours. It finally detached on approach to LHR, no doubt landing in someone's garden and causing them to go "huh?"

A similar thing happened on a 32x. The inboard canoe has a seal where it meets the trailing edge. When the flaps were down, this seal was flapping about. When the aircraft was cleaned up, the seal stopped was squeezed and stopped flapping so they would not have seen the problem on a walkaround.

"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo

Cabin crews observations can certainly be useful on some occasions
Example...
On pushback at the old RUH airport years ago, in the L1011, the CC chief mentions that the floor in the rear of the cabin is VERY hot.
F/E says, not to worry...it IS hot outside, temp 49C.
OTOH, the Captain (yours truly) thinks otherwise, and returns to the parking stand for investigation.
Result?
An N3 bleed air leak is found coming from the number two engine and has, at this point, burned through a wire bundle.
The AEEA overheat light is illuminated as well.
The F/E never noticed this.

Quoting BAe146QT (Thread starter):
So, has anyone here - private pilot or otherwise - ever had information from the FAs or the customers that has been helpful?

So far no, but I'd want FAs or passengers to speak up if they see something obviously unsafe like fire or smoke.

This topic reminded me of a common occurrence on the Dash 8. The brakes have a tendency to spark and glow at night due to the heat built up in them from landing and taxiing to the parking area. Often times passengers will inform the pilots or flight attendants that they should check the brakes because they saw sparks coming from them after landing. Hearing a comment like that all the time would get annoying, but I'd rather the passengers speak up in that instance, then have them all be silent on the day the brakes catch on fire.

Quoting KELPkid (Reply 3):
I went through my GUMP check (Gear, Undercarriage, mixture, prop) which is standard for a high-performance complex single.

Wouldn't Gear and Undercarriage be the same thing? I always taught it as Gas, Undercarriage, Mixture, Prop. Gas was for fuel selector to fullest tank and auxiliary pump on.

The issue of mixture before landing at high altitudes is interesting. Most POHs for piston powered aircraft will say to set the mixture to full rich before landing, but will instruct pilots to lean the mixture before takeoff in order to achieve maximum performance. Doesn't seem to make a lot of sense to me. Perhaps a topic for a future thread.

edit for crappy spelling

[Edited 2007-06-03 09:06:55]

It is a mistake to think you can solve any major problems with just potatoes.

You will find, Alias1024, many misunderstandings/varied opinions on the part of most general aviation pilots about just what to do with engine mixtures and constant speed props on descent/approach...IE: many old wives tales.

Having said this, the pilot operating handbooks that came with many of these airplanes, were rather less than desirable in many respects.

A clue as to how these items should be handled can many times be taken from the operation of large piston engined airliners of yesteryear.

For example, lets look at one type, the Boeing Stratocruiser.
I flew these for a short while an the procedure was thus...

Descent.
Engine mixtures left in the autolean position.
Propeller RPM's left in the cruise position.

Approach for landing.

Engine mixtures left in the autolean position.
Propeller RPM's left in the cruise position.

Keep in mind that the movement of the engine mixture controls toward autorich, did not necessarily provide sea level/full power enrichment...as the pressure carburetors on these aircraft were altitude compensating, the actual airport elevation was the determining factor.

The propellor controls were absolutely never ever moved abruptly toward the low pitch/high RPM position, on short final, as many pilots do now with their GA airplanes.
Rather, the stephead electric motors on the propellor governors were slowly toggled toward high RPM, just as the airplane was about to touch down.

If, on the other hand, a go-around was desired/required, the Flight Engineer would slowly toggle the props toward the high RMP position, just as engine throttles were advanced...IE: a co-ordinated effort, by crew members.

Now, some might ask...just why was it done this way?

It was because, earlier on with other engines, it was found that advancing the propeller controls toward the high RPM position far too early in the approach, created excessive master rod bearing wear, as well as piston ring float...both conditions were expensive to fix.

Quoting 411A (Reply 15):many misunderstandings/varied opinions on the part of most general aviation pilots about just what to do with engine mixtures and constant speed props on descent/approach...IE: many old wives tales.

Not too long ago, 411A, you described how shock cooling is an old wives tale.

If I remember correctly (and please correct me if I've got it wrong), so-called "shock cooling" is not a result of quickly pulling the throttles to idle in cold air. Rather, it's a result of quickly enrichening the mixture after a long descent, and introducing large amounts of ice-cold fuel to a warm engine.

Not so much of a problem with the smaller GA opposed engines, but a rather big one with the larger displacement fuel injected engines...TCM TSIO520, GTSIO520...Lycoming IGSO480/540 models.
In addition, although GA opposed engines don't have master rod bearings and ring flutter is not a particular problem with these engines, to increase rapidly the engine RPM without good reason will severely wear the engine bifler pendulum damper (counterweight) bushings, which, in the extreme, will end up with a counterweight chucked right trhough the engine case.

As you might imagine, this is definitely not a good thing.

Read....EXPENSIVE.

Treat your larger engines carefully, and they will serve you well.

How well?

An example can be gained from some time ago, with Prinair, flying re-engined deHavilland Herons (4 x IO-520's) where the time between overhauls was FAA approved to 4000 hours.

Yes, quite true.
4000 hours.

Careful engine management is the key to long engine life, with the larger models.
True yesterday with the big radials, true today with the larger (especially geared) engines in use.

Interesting stuff, 411A. I've always been amazed at how many pilots abruptly thrash their throttles in and out. Particularly during the run-up.

One of my past 172 checklists called for a brief full-throttle segment of the runup, and it seemed as though I was the only one who would reduce the throttle to idle in a very slow, smooth manner. Everyone else would just chop it to idle in one quick motion.

I'm not sure how detrimental that actually is, but as far as I'm concerned, it feels a lot better to treat the engine with respect and care.

Quoting 2H4 (Reply 18):Interesting stuff, 411A. I've always been amazed at how many pilots abruptly thrash their throttles in and out. Particularly during the run-up.

One of my past 172 checklists called for a brief full-throttle segment of the runup, and it seemed as though I was the only one who would reduce the throttle to idle in a very slow, smooth manner. Everyone else would just chop it to idle in one quick motion.

I'm not sure how detrimental that actually is, but as far as I'm concerned, it feels a lot better to treat the engine with respect and care.

That sounds like common sense to me. Same with car engines. Gentle movements of the throttle will make the engine wear less.

Quoting 411A (Reply 15):If, on the other hand, a go-around was desired/required, the Flight Engineer would slowly toggle the props toward the high RMP position, just as engine throttles were advanced...IE: a co-ordinated effort, by crew members.

The interesting part here is that even in a go-around, there are no hurried movements. I guess if you plan correctly, you don't have to stress the aircraft.

"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo

Quoting Alias1024 (Reply 14):Wouldn't Gear and Undercarriage be the same thing? I always taught it as Gas, Undercarriage, Mixture, Prop. Gas was for fuel selector to fullest tank and auxiliary pump on.

I realized that after I posted it, I put the wrong thing for "G". G-Gas, fullest tank. My bad. I was only up until 1:45 the morning before I made that post

Quoting 2H4 (Reply 18):Interesting stuff, 411A. I've always been amazed at how many pilots abruptly thrash their throttles in and out. Particularly during the run-up.

A Lycoming O-360 will reward such abuse by hamfisted pilots with a very loud backfire that everyone on the field will hear Remember, this engine has as much displacement per cylinder as the monstrous IO-540...

Quoting Alias1024 (Reply 14):The issue of mixture before landing at high altitudes is interesting. Most POHs for piston powered aircraft will say to set the mixture to full rich before landing, but will instruct pilots to lean the mixture before takeoff in order to achieve maximum performance. Doesn't seem to make a lot of sense to me. Perhaps a topic for a future thread.

At my school they taught us to always lean the mixture unless you're below 3000 msl, at which point you would just put it full rich. Our rule of thumb for the C172 is half a turn for every 1000 ft up. It is actually pretty accurate, when I lean for best power during cruise its usually no more than 2 turns away. Works just as well going down.

It works so well our engines are being overhauled every 2700 hrs, and they are trying to get approval for every 3000 hrs. Not bad considered the abuse our engines get with all the students going through them.

RE: Throttle movement
Where I'm flying we're taught the two second rule. That means at least two seconds between idle power and full power, and visa versa. General rule with most things, if you look after something it lasts longer.